• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.930-933
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• 2003

The electrochemical oxidation of ascorbic acid(AA), serotonin(StT) and epinephrine(EP) have been performed ae poly N,N-dimethylanliline(PDMA) film coated diamond electrode. This cationic polymer film is electrochemically deposited on boron-doped diamond electrode surface. Unlike the bard electrode, the polyaer film-coated diamond electrode can well separate the oxidation potential of AA by 330mV. Thus this electrode can be successfully used for the simultaneoud detection of both species. Increases in the concentration of AA donot affect the reponse of EP and ST.

• Korean Journal of Veterinary Service
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• v.41 no.4
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• pp.287-289
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• 2018

This study was conducted to investigate the detection of various vector-borne pathogens in such cats. A total of 48 stray cats collected in Daejeon were included in this study. The total positive rate of hemotropic mycoplasmas and Babesia spp. was 25% and 4%, respectively. It is recommended that species-level classification of hemotropic mycoplasmas and Babesia spp. is needed and that a large-scale prevalence study of infectious agents in all the regions of South Korea be conducted.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.132-133
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• 2003

The marine dinoflagellate genus Alexandrium comprise PSP producing A. acatenella, A. angustitabuzatum, A. catenella, A. fundyense, A. minutum, A. ostenfezdii, A. tamiyavanichii and A. tamarense. In monitoring toxic Alexandrium, rapid and exact species identification is one of the significant prerequisite work, however we have suffered confusion of species definition in Alexandrium. To surmount this problem, we chose DNA probing, which has long been used as an alternative for conventional identification methods, primarily relying on morphological approaches using microscope in microbial field. Oligonucleotide DNA probes targeting rRNA or rDNA have been commonly used in diverse studies to detect and enumerate cells concerned as a culture-indetendent powerful tool. Despite of the massive literature on the HAB species containing Alexandrium, application of DNA probing for species identification and detection has been limited to a few documents. DNA probes of toxic A. tamarense, A. catenella and A. tamiyavanichii, and non-toxic A. affine, A. fraterculus, A. insuetum and A. pseudogonyaulax were designed from LSU rDNA D1-D2, and applied to whole cell-FISH. Each DNA probes reacted only the targeted Alexandrium cells with very high species-specificity within Alexandrium. The probes could detect each targeted cells obtained from the natural sea water samples without cross-reactivity. Labeling intensity varied in the growth stage, this showed that the contents of probe-targeted cellular rRNA decreased with reduced growth rate. Double probe TAMID2S1 achieved approximately two times higher fluorescent intensity than that with single probe TAMID2. This double probe did not cross-react with any kinds of microorganisms in the natural sea waters. Therefore we can say that in whole-cell FISH procedure this double DNA probe successfully labeled targeted A. tamiyavanichii without cross-reaction with congeners and diverse natural bio-communities.

• Parasites, Hosts and Diseases
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• v.52 no.5
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• pp.471-478
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• 2014

Trichomonad species inhabit a variety of vertebrate hosts; however, their potential zoonotic transmission has not been clearly addressed, especially with regard to human infection. Twenty-one strains of trichomonads isolated from humans (5 isolates), pigs (6 isolates), rodents (6 isolates), a water buffalo (1 isolate), a cow (1 isolate), a goat (1 isolate), and a dog (1 isolate) were collected in Indonesia and molecularly characterized. The DNA sequences of the partial 18S small subunit ribosomal RNA (rRNA) gene or 5.8S rRNA gene locus with its flanking regions (internal transcribed spacer region, ITS1 and ITS2) were identified in various trichomonads; Simplicimonas sp., Hexamastix mitis, and Hypotrichomonas sp. from rodents, and Tetratrichomonas sp. and Trichomonas sp. from pigs. All of these species were not detected in humans, whereas Pentatrichomonas hominis was identified in humans, pigs, the dog, the water buffalo, the cow, and the goat. Even when using the high-resolution gene locus of the ITS regions, all P. hominis strains were genetically identical; thus zoonotic transmission between humans and these closely related mammals may be occurring in the area investigated. The detection of Simplicimonas sp. in rodents (Rattus exulans) and P. hominis in water buffalo in this study revealed newly recognized host adaptations and suggested the existence of remaining unrevealed ranges of hosts in the trichomonad species.

• Ocean and Polar Research
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• v.32 no.2
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• pp.113-122
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• 2010

Understanding the abundance and distribution of massive jellyfish is necessary to forecast where or when their blooms will happen. The acoustic technique is one of the most useful methods of obtaining information if the acoustic characteristics of the targets are known. This study was conducted to determine the acoustic target strength (TS, dB) of two jellyfish species, Aurelia aurita and Cyanea nozakii, in the southern coast of Korea. For the ex situ measurements, 120, 200, and 420 kHz split beam transducers were used, and jellyfish with various bell lengths were arranged to prepare multiple jellyfish. Under 2 vertical individuals, the mean TS for multiple A. aurita at 120, 200, and 420 kHz was -72.7, -71.7, and -68.2 dB, respectively. In the case of 5 vertical individuals, the mean TS of the species was -71.3, -68.2, and -62.0 dB. Finally, the mean TS of C. nozakii at 120, 200, and 200 kHz was -62.0, -60.3, and -58.2 dB under 2 individuals and -58.1, -57.4, and -54.0 dB under 4 individuals, respectively. For both species, higher numbers of jellyfish resulted in a higher TS. In addition, higher frequencies were associated with a higher TS for the same jellyfish. These TS results for two species can be used as essential data for the acoustic detection of jellyfish in an open ocean or coastal area.

• Journal of Life Science
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• v.9 no.1
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• pp.69-75
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• 1999

Four species belonging to the Drosophila melanogaster complex were examined genetically and morphologically to analyze interspecific relationships. Insemination rates ranged from 96% to 99% within species crosses, but interspecific crosses among the four species exhibited a great variations in the frequency of successful matings. D. melanogaster females mated relatively well with males of other species and D. sechellia males were more successful in mating with females of other species. In the crosses among D. simulans, D. mauritiana and D. sechellia, hybrid flies were fertile in females, but sterile in males regardless of reciprocal matings. The phenogenetically relationship between this complex and their hybrids were investigated by the comparison of sex comb tooth number and genital arch of male. They were controlled by polygenic factors on the chromosome of both parents. The effects of temperature on viability of hybrids between D. melanogaster females and D. simulans males were investigated for detection of genes concerning the speciation. The temperature sensitivity of the hybrid was mainly controlled by genes located on the X chromosome of D. simulans males.

• Korean journal of applied entomology
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• v.29 no.1
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• pp.14-19
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• 1990

Nematodes and insects associated with dead trees were surveyed on the 238 dead trees belonging to 19 tree species in Pusan, Gyeongnam, Gyeongbuk, Chunnam, and Chonbuk provinces from April to September of 1989. Pine wood nematode, Bursaphelenchus xylophilus was found only in Pusan but B. mucronatus was collected at Chinju and Chinhae. The 13 nematode species in 9 genera were identified. Out of them, Diplogasteroides dimidius, Rhabdontolaimus adephagus, R. janae, Mikoletzkya diluta, M. ruminis, M. langcaudaa, Parasitorhabditis hylurgi, Panagrolaimus concolor, Panagrodontus dentatus, Prothalonema intermedium, and marcrolaimus canadensis were recorded for the first time in Korea. Insects collected from dead trees were 5 orders, 9 families, 25 genera, and 27 species. of them, the Coleoptera were the most collected insects by the 3 families, 19 genera and 22 species. The Scolytidae were 12 species in 10 genera. Hypothenemus eruditus was firstly collected from Campylotropis macrocarpa, Lespedeza maximowizi, Forsythia ovata, Meliosma oldhami, Securinega suffruticosa, Broussonetia kazinoki, and Cornus walteri. The maximum number of pine wood nematode was separated from the abdomen of Monchamus alternatus, the pine woodnematode vector. The maximum number of nematodes per an adult of M. alternatus was 127,535, minimum 2,616, and average 42,817.

• Mycobiology
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• v.30 no.2
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• pp.82-87
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• 2002

Species of Phellinus were known to harmful fungi causing white pocket rot and severe plant disease such as canker or heartrot in living trees in the West, but some species have been used to traditional medicines in the Orient for a long time. In this study the partial D1-D2 nucleotide sequences of 28S ribosomal DNA from 13 Phellinus strains were determined and compared with the sequences of 21 strains obtained from GenBank database. According to the neighbor-joining(NJ) method comparing the sequence data the phylogenetic tree was constructed. The phylogenetic tree displayed the presence of four groups. Group I includes P. ferreus, P. gilvus and P. johnsonianus, Group II contains P. laevigatus, P. conchatus and P. tremulae, Group III possesses P. linteus, P. weirianus, P. baumii, P. rhabarbarinus and P. igniarius, and Group IV comprises P. pini, P. chrysoloma. P. linteus and P. baumii, which were used mainly in traditional medicine, belong to the same group, but exactly speaking both were split into two different subgroups. To detect P. linteus only, we developed the PCR primer, D12HR. The primer showed the specific amplification of P linteus, which is permitted to medicinal mushroom in the East. The results make a potential to be incorporated in a PCR identification system that could be used for the rapid identification of this species from its related species, P. linteus especially.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.496-503
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• 2021

Background: Considering the expenses of and difficulties in arsenic speciation by high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS), alternative measurement methods should be useful, especially for large-scale research and projects. Objectives: A measurement method was developed for arsenic speciation using HPLC-atomic fluorescence spectrometry (HPLC-AFS) as an alternative to HPLC-ICP-MS. Methods: Total arsenic and toxic arsenic species in some seafoods were determined by atomic absorption spectrometry coupled with hydride vapor generation (AAS-HVG) and HPLC-AFS, respectively. Recovery rate of arsenic species in seafood was evaluated by ultra sonication, microwave and enzyme (pepsin) for the optimal extraction method. Results: Limits of detection of HPLC-AFS for As³⁺, dimethylarsinate (DMA), monomethylarsonate (MMA) and As⁵⁺ were 0.39, 0.53, 0.60 and 0.64 ㎍/L, respectively. The average accuracy ranged from 97.5 to 108.7%, and the coefficient of variation was in the range of 1.2~16.7%. As³⁺, DMA, MMA and As⁵⁺ were detected in kelp, the sum of toxic arsenic in kelp was 40.4 mg/kg. As³⁺, DMA, MMA and As⁵⁺ were not detected in shrimp and squid, but total arsenic (iAS and oAS) content in shrimp and squid analyzed by AAS-HVG were 18.1 and 24.7 mg/kg, respectively. Conclusions: HPLC-AFS was recommendable for the quantitative analysis method of arsenic species. As toxic arsenic species are detected in seaweeds, further researches are needed for the contribution degree of seafood in arsenic exposure.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.508-513
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• 2008

Erythromycin has been used to treat Streptococosis, Edwardsiel1osis, Vibriosis, Bacterial enteritis in the cultured fish. In this study, a rapid and effective erythromycin analysis method with new sample treatment protocol and liquid chromatography/tandem mass spectrometry (LC/MS/MS) system for fish products was developed. For the erythromycin extraction from fish muscle, the solvent mixture composed of 0.2% meta-phosphoric acid and methanol (6:4) showed good recovery rate, and the optimum extraction solvent volume was 20 mL. Erythromycin detection using LC/MS/MS were carried out under electro spray ionization (ESI) positive condition and erythromycin mass value 576.2 and 157.9. And the detection limit of the established method was 0.005 mg/kg in fish products. The recovery rate of the developed method applied to the fish species were as following, olive flounder, $87.6{\pm}5.0%$; black rockfish, $87.2{\pm}6.4%$; eel, $85.2{\pm}4.8%$; and rainbow trout, $86.0{\pm}6.2%$. In the established method in this study, the correlation of coefficient values ($R^2$) of erythromycin calibration curve (n=11) was 0.9998.